2. The spaces and the significance of the spaces in which strangers interact, and

3. How strangers 'read' each other, how they initiate interactions, how they avoid interactions, how they trust each other and how they fool each other, how they watch, listen and follow each other.

Then there is the secret theme. I want students to fall in love with talking to strangers, to do it more, and to make technology that creates more plentiful and meaningful interactions among strangers."